Fungicidal composition containing 2-isoxazolin-5-one and method of using the same

ABSTRACT

The present invention is directed to the novel fungicidal compositions containing 2-isoxazolin-5 and one method using the same.

United States Patent 151 3,683,087 Geoghegan et al. 1451 Aug. 8, 1972[54] F UNGICIDAL COMPOSITION CONTAINING Z-ISOXAZOLIN-S-ONE [52] US. Cl..424/272, 99/ l 53 ND METH OF USING THE SAME [51] Int. Cl. ..A01n 9/22,AOln 9/28 [72] Inventors: Michael Joseph Augustine [58] v Fleld ofSearch ..l67/33 A, 424/272; 99/153 Geoghegan; John Angus William Turner;Peter Frank Hilary [56] References Cited Freeman, all of Bracknell,England; UNITED STATES PATENTS L'Q Q S fS? New 3,312,690 4/1967 Masudam1 ..424/272 x 3,326,931 6/1967 Narayanan et al.....424/272 X [73]Assignee: Imperial Chemical Industries Limited, London, England PrimaryExaminerAlbert T. Meyers Assistant Examiner-D. R. Mahanand [22] Ffled'1967 Attorney-Cushman, Darby & Cushman 21 Appl. No.2 647,576

57 ABSTRACT Related US. Application Data rh d d h l f [60] Division ofSet. N0. 433,l62, Feb. 16, 1965, e present memo" ecte to t e un- Pat.No. 3,370,064, which is a continuation-inpart of Ser. No. 147,741, Oct.16, 1961, abandoned.

gicidal compositions containing 2-isoxazolin-5 and one method using thesame.

20 Claims, N0 Drawings FUNGICIDAL COMPOSITION CONTAINING 2-ISOXAZOLIN-S-ONE AND METHOD OF USING THE SAME This application is adivision of our copending application, Ser. No. 433,162, filed Feb. 16,1965 (US. Pat. No. 3,370,064) which is a continuation-in-part of SerialNo. 147,741, filed Oct. 26, 1961, now abandoned.

This invention relates to the use as fungicides of 2- isoxazolin-S-ones,to new 2-isoxazolin-5-ones and to processes for their preparation.

The invention includes fungicidal compositions comprising as activeingredient a 2-isoxazolin-5-one of the formula:

where R is a carboxymethyl or carboxyethyl radical, or an alkyl radicalof one to six carbon atoms (especially one to four carbon atoms), suchas methyl, ethyl, propyl and butyl, optionally having a substituenthydroxy or cyano group or a halogen atom and R, is a substituted orunsubstituted phenyl or naphthyl radical, and a carrier for the activeingredient, said carrier comprising a solid inert diluent, or a liquiddiluent containing a surface active agent.

Where the group R is a substituted phenyl or naphthyl radical thesubstituents can be, for example, one or more of the following: alkyland alkoxy radicals of from 1 to l2 and especially from one to fourcarbon atoms, cycloalkyl, aryl, (or substituted aryl), arylazo (orsubstituted arylazo), aryloxy, halogen, carboxy, alkoxycarbonyl,carboamino, cyano, nitro, hydroxy], trifluoromethyl, amino,N-alkylamino, N,N-dial kylamino, sulphonic acid, sulphonamido,aminosulphonyl or thiocyanate radicals.

It has been found that compounds where the group R is achloro-substituted phenyl radical or a lower alkyl-substituted phenylradical possess useful fungicidal properties as is shown in theExamples. Examples of di-substituted phenyl radicals are those in whichthe substituents are two alkyl or two alkoxy radicals, two atoms of anyof the halogens, alkyl and alkoxy, alkyl and nitro, alkoxy and nitro,alkyl and halogen or alkoxy and halogen.

The compound used as active ingredient can if desired be in the form ofone of its salts, for example its sodium or potassium salt.

Some of the compounds of the invention have been found to be veryeffective when applied as foliage fungicides, some when applied asseed-dressings and some as soil fungicides; and the exact form of thefungicidal composition depends to a large extent upon the use to whichthe composition is to be put and the pathogen which it is wished tocontrol. For example, the compositions can be powders, solutions,dispersions or pastes. Where they are powders they can be ones in whichthe active ingredient is in admixture with a powder diluent. Wherethe-composition is liquid it can be one in which the active ingredientis dissolved or suspended in a suitable liquid, for example water or asuitably non-phytotoxic liquid. The ingredients used with the activeingredient in any of the fungicidal compositions of this invention canbe substances known to the art as being suitable in the formulation offungicidal compositions, for example surface active substances such aswetting and dispersing agents, binders, stickers, corrosion inhibitorsand stabilizing agents.

F ungicidal compositions of the invention which have been found to beuseful as liquid seed dressings are solutions of the sodium salt of3-methyl-4-phenylhydrazono-2-isoxazolin-5-one in B-ethoxyethanol,diacetonyl alcohol or ethylene glycol, and in particular solutions inwhich the sodium salt is present in at proportion of about 25% w/v.

The invention also consists in the new 2-isoxazolin-5- ones of thegeneral formula:

where R is an alkyl radical of 2-6 (especially 2-4) carbon atoms,acarboxyalkyl or alkoxycarbonylalkyl radical of not more than fourcarbon atoms, and R is a substituted or unsubstituted phenyl or naphthylradical; or where R is an alkyl radical of l 6 (especially one to four)carbon atoms or a carboxyalkyl or alkoxycarbonylalkyl radical of notmore than four carbon atoms and R is a chloro-substituted phenylradical; and their salts.

The .2-isoxazolin-5-ones useful as active ingredients in the fungicidalcompositions of his invention can be obtained, for example, by a processin which there is reacted together a keto-ester of the formula:

R CO CH COOR where R is an alkyl radical of 1-6 (especially one to four)carbon atoms or a carboxyalkyl or an alkoxycarbonylalkyl radical of notmore than four carbon atoms and R is an alkyl radical of one to fourcarbon atoms, the appropriate substituted or unsubstituted phenyl ornaphthyl diazonium salt and hydroxylamine or a salt of hydroxylamine.The process is conveniently performed with the reactants dissolved ordispersed in water or in a mixture of water and ethanol. The diazoniumsalt can be conveniently produced in situ by the reaction of theappropriate amine and nitrous acid as is illustrated in the Examples ofthis specification.

A second process for the preparation of the 2-isoxazolin-S-ones is onein which an azo compound of the formula:

where R and R have the meanings given to them in connection with thefirst process described above and R is a substituted or unsubstitutedphenyl or naphthyl radical, is reacted with hydroxylamine or a saltthereof. This process is conveniently carried out in mildly alkalineconditions, for example with the reactants dissolved or dispersed inwater or in a mixture of water and ethanol and in the presence ofcaustic alkali or sodium acetate, or in pyridine. Since reaction at roomtemperature is generally slow the process is preferably carried out atan elevated temperature, for example at a temperature in the range60-115 C. The azo compound used in this second process can convenientlybe obtained in situ by the reaction of a keto-ester of formula:

RCOCl-l COOR and the appropriate diazonium salt.

In the preparation of compounds of this invention where the group R is amethyl group satisfactory results have been obtained using diketeneinstead of the ketoester.

The invention also consists in a method of combating plant pathogens, inwhich the foliage of a plant susceptible to such pathogens, seed fromwhich the plant can be grown or soil in which the plant is to be grown,is treated with a compound or fungicidal composition asherein-described.

The invention is illustrated by the following Examples:

EXAMPLE 1 Ethyl acetoacetate (6.6 g.), hydroxylamine hydrochloride (3.5g.), m-toluidine (5.4 g.) and concentrated aqueous hydrochloric acid 10ml.) were mixed with water (25 ml.) and the mixture was cooled to aboutC. A cold aqueous solution of sodium nitrite (4.0 g.) in water ml.) wasadded slowly to the mixture with stirring, care being taken that thetemperature did not rise above 10 C. The mixture was then stirred for 6hours, the temperature being allowed during this time to rise slowly toabout 20 C, and filtered. The solid residue which was obtained on thefilter was washed with water and crystallized from a mixture of ethanoland benzene. The product thus obtained was 3-methyl-4-(3-methylphenyl-hydrazono-Z-isoxazolin -5 one, as yellowcrystals, m.p. 172 C.

EXAMPLE 2 3-Chloro-4-methylaniline (7.1 g.) was suspended in water (60ml.) and the mixture acidified with concentrated aqueous hydrochloricacid (18 ml.). After cooling to 5 C. the mixture was diazotized with asolution of sodium nitrite (4.0 g.) in water ml.). The solution soobtained was then added slowly with stirring to a cold (5 C.) mixture ofethyl acetoacetate (6.6 g.) in ethanol (170 ml.) and water (45 ml.) towhich had been added anhydrous sodium acetate, (24 g.). The mixture wasallowed to stand at about C. for 15 hours, filtered and the solidresidue obtained on the filter washed with water. The residue wasdissolved in boiling ethanol 100 ml.) and to this solution there wasadded slowly a hot solution of hydroxylamine hydrochloric (3.5 g.) inwater (100 ml.) to which had been added anhydrous sodium acetate (8.2g.). The mixture so obtained was heated under reflux for 15 minutes,allowed to stand for 15 hours at about 20 C and filtered. The solidresidue which was obtained on the filter was washed with water andcrystallized from ethanol. The product thus obtained was 3-methyl-4-(3-chloro-4-methylphenylhydrazono-2-isoxazolin-5-one as yellow crystals,m.p. 192 C.

EXAMPLES3-33 A number of other 2-isoxazolin-5-ones have been prepared bythe general methods described above in Examples 1 and 2, but using theappropriate amine in each instance instead of m-toluidme and 3-chloro-4-methylaniline used respectively in those Examples. These other2-isoxazolin-5-ones are set out in the table below as Examples 3-33. Theproducts of Examples 10 3-15 were obtained by the process of Example 1while those of Examples 16-33 were obtained by the process of Example 2.The products of Examples 3-33 are believed to all have the generalformula:

1 1 15 o1I=-(: |3=NNR1 where R is a substituted benzene ring and theproducts 20 are identified in each Example by the meaning given to R inthe column having that heading. for the sake of convenience the doublebonds have been omitted from all the benzene rings shown. The meltingpoint shown against each product is that obtained using a sample of theproduct which had been purified by recrystallization.

TABLE 1 Product Example M.P. N0 1 0.) Appearance 3 0M0 193 Yellow O|crystals.

4 20a 0 OM0 335E215.

5 M0 150 Do.

6 192 Yellow *Cl crystals.

8 M0 142 Do. Me

n mo 140 Do.

11 OZN 214 Yellow crystals.

12 M0 199 Do.

13 Mo Mu 136 Orange crystals.

Table l- Continued Product Example M.l. No. 1 0.) Appearance 14 N 2 205Brown C l crystals.

15 M0 128 Orange I crystals.

16 BIIO 148 Do.

17 Ill/1e 171 Do.

I Me

18 Cl 193 Yellow I crystals.

19 B r 163 Brown Ol crystals.

20 Me 01 194 Yellow crystals.

21 (I31 148 Do.

23 (3E1 182 Do.

24 IVIIe 168 Do.

25 B 1 145 Do.

26 165 Orange F crystals.

27 F 200 Yellow crystals.

29 Fir 182 Red crystals.

30 (3 F3 198 Orange @I crystals.

31 (J O lCt 96 Yellow crystals.

3.! EtOO (I) D0.

33 Q q 208 Brick-{old N:N- ljlYS 8. S.

EXAMPLE 34 ethylacetoacetate (6.6 g.), hydroxylamine hydrochloride (3.5g.),m-chloroaniline (6.4 g.) and concentrated aqueous hydrochloric acid(10 ml.) were added to ethanol (10 ml.) and the mixture cooled to about5 C. A cold aqueous solution of sodium nitrite (4.0 g.) in water 10 ml.)was added slowly to the mixture with stirring so that the temperaturedid not exceed 10 C. The mixture was then stirred for a further 6 hours,the temperature being allowed during this time to rise slowly to about20 C., and filtered. The solid residue which was obtained on the filterwas washed with water and crystallized from a mixture of ethanol andbenzene. The product thus obtained was 3-methyl-4-(3'-chlorophenylhydrazono)-2-isoxazolin-5-one as brown crystals, m.p.162 C.

EXAMPLE 35 p-Ethylaniline (6.1 g.) was suspended in water (60 ml.) andthe mixture acidified with concentrated aqueous hydrochloric acid (18ml.). After cooling to 5 C. the mixture was diazotized with a solutionof sodium nitrite (4.0 g.) in water 15 ml.). The resulting solution wasadded slowly with stirring to a cold (5 C.) mixture of ethylacetoacetate (6.6 g.) in ethanol ml.).and water (45 ml.) to which hadbeen added anhydrous sodium acetate (24 g.). The mixture was allowed tostand at about 20 C. for 15 hours and the heavy oil which was obtainedwas separated from the aqueous layer and washed with water. The washedoil was dissolved in boiling ethanol (100 ml.) and to this solutionthere was added slowly a hot solution of hydroxylamine hydrochloride(3.5 g.) in water 100 ml.) to which had been added anhydrous sodiumacetate (8.2 g.). The mixture so obtained was heater under reflux for 15minutes, allowed to stand for 15 hours at about 20 C. and filtered. Thesolid residue which was obtained on the filter was washed with water andcrystallized from ethanol. The product thus obtained was 3-methyl-4-(4'-ethylphenylhydrazono)-2-isoxazolin-5-one as yellow crystals, m.p. 154C.

EXAMPLE 36 The process described in Example 35 was repeated except thatthe p-ethylaniline (6.l g.) was replaced by o-ethylaniline (6.1 g.). Theproduct when crystallized from ethanol was3-methyl-4-(2-ethyl-phenylhydroazono)-2-isoxazolin-5-one as orangecrystals, m.p. 122 C.

Examples 37, 38 and 39 describe the preparation of various salts of2-isoxazolin-5-ones.

3-Methyl-4-(3'-methylphenylhydrazono)-2-isoxazolin-S-one (3 g. of thecompound obtained as the product of Example 1 above) was suspended in 10percent aqueous sodium hydroxide solution (30 ml.) and ethanol (30 mo.)was added. The mixture was heated at about 80 C. for 2 minutes and theresultant solution was filtered. On cooling the resulting filtrate, acrystalline solid precipitated which was removed by filtration and waswashed with ether. The product thus obtained was the sesquihydrate ofthe sodium salt of 3-methy1-4- (3-methylphenyl-hydrazono)-2-isoxazo1in-5-one as yellow needles whichslowly decomposed on heating but were not completely fused at 300 C.

EXAMPLE 38 The process described in Example 37 was repeated except thatthe 3-methy1-4-(3-methylpheny1- hydrazono)-2-isoxazolin-5-one (3 g.) wasreplaced by 3-methyl-4-(4'-chloropheny1hydrazono)-2-isoxazolin- 5-one (3g. of the compound obtained as product of Example 6 above). The productwas the trihydrate of the sodium salt of 3-methyl-4-(4'-chloropheny1-hydrazono)-2isoxazo1in-5-one as yellow crystals, m.p. 170 C. withdecomposition.

EXAMPLE 39 The process described in Example 37 was repeated except thatthe 3-methy1-4-(3-methylphenylhydrazono)-2-isoxazolin-5-one (3 g.) wasreplaced by 3-methyl-4-(4'-chlorophenylhydrazono)-2-isoxazolin- 5-one (3g. of the compound obtained as product of Example 6 above) and the 10percent aqueous sodium hydroxide (30 ml.) by 10 percent aqueouspotassium hydroxide (30 ml. The product was the sesquihydrate of thepotassium salt of 3-methy1-4-(4'-ch1oropheny1-hydrazono)-2-isoxazolin-5-one as yellow crystals which decomposed at170l 80 C.

EXAMPLE 40 This Example describes the preparation of 3-methy1-4-(2':4':5'2-isoxazo1in-5- one by a process which is a modification ofthe general process described in Example 2 above. The modificationconsists essentially of the use of pyridine, in place of ethanol, in theprocesss third stage where the product of the diazonium salt and theketo-ester is reacted with hydroxylamine hydrochloride.

The wet, crude intermediate (23 g.) obtained by reacting ethylaceto-acetate (6.5 g.) with 2:4:5- trichlorophenyl-diazonium chloride bythe general method of Example 2 was mixed with hydroxylaminehydrochloride (3.5 g.) and pyridine (75 ml.) and the mixture wasrefluxed for 1 hour. The product obtained was then poured into icedwater containing hydrochloric acid and the solid which precipitated wasremoved by filtration and recrystallized from ethanol yielding 3-methyl-4-(2'14'z52-isoxazolin-S-one as a reddish-brown solid, mp. 151 C.

EXAMPLES 41 78 A number of other 2-isoxazolin-5-ones have been preparedby the general method described in Examples l, 2 or 40 above, but usingvarious keto-esters and the appropriate amine in each instance. These2-isoxazolin-S-ones are set out in Table II below as Examples 41 78.

The products of Examples 41 78 were obtained by processes involving aketo-ester of the formula: R-CO CH COOEt and a diazonium chloride offormula: ClN N-R and are believed to all have a structure correspondingto the general formula:

N o=o where R is an alkyl or alkoxycarbonylalkyl radical and R is asubstituted benzene ring.

In Table 11 the product of each Example is identified by reference tothe nature of the groups R and R and for the sake of convenience thedouble bonds have been omitted from all the benzene rings depicted.

With the exceptions of Examples 52, 67, 68, 72, 73, 7S and 76, thecompounds of all the Examples in Table 11 were obtained using thegeneral process described in Example 2 above, but using the appropriateketo-ester and amine in each instance. With regard to the exceptions,the compounds of Examples 67 and 68 were obtained by the general processof Example 1 above; and the compounds of Examples 52, 72, 73, 74 and 76by the general process of Example 40, using the appropriate keto-esterand amine in each instance.

Table ll Product ample .\1.I.

No. R R C.)

| "G ll nC4I'Iv nC1zH25 45 CH; Q 162 OCzH5 COOCzH SOQNlI 61 CH Q 199 SCNTable ll-Continued Product Exampl M.P. No. R R1 54 CH3 ocllzHn 151OCzHlS 55 CH (H'llzHs 176 iY. 56 CH3 0031116) 124 OCaH7(1) 57 CH3 OCIIIa187 OCH;

l CH

59 CH: OCzHs 151 60 CH3 CH3 (Ill-I3 127 63 CH N0 175 OCH:

Ulla

QOCFO EXAMPLES 79 88 Table [II below includes as Examples 79 88 a numberof further 2-isoxazolin-5-ones which have been formulated as fungicidalcompositions. The various compounds are identified in Table III, as inTables I and ll, by reference to the nature of the groups R and R Thedouble bonds have, for convenience, been omitted from all the structuresdepicted.

Table 111- Continued Example No.- R R M.P. C.)

1 With decomposition.

Good results have been obtained using fungicidal compositions of thisinvention as seed dressings, and in Table IV below there is showncompounds which have been found to be active against a number ofeconomically important fungus and bacterial diseases. Similarly, Table Vshows compounds found to be active against various foliage fungusdiseases. The active ingredients of the compositions tested have beenreferred to below, for simplicity, by the number of the Examples inTables I, II or 111 in which they appear.

Seed Dressings TABLE IV Disease Crop Active Ingredient the product ofExample Nos.

Pythium ultimum Peas 5, ll, 16, 17,79 and 8| Fusarium culmorum Peas 6,7, 10, 26 and 81 Xanthomonas malvacearum Cotton 22 Tilletia caries Wheat6, 82 and 84 Foliage Fungicides TABLE V Disease Crop Active Ingredientthe product of Example Nos.

Pirisularia Rice 6, 7, 20, 36 and 85 oryzae Plasmopara Vines 7 viticolaErysiphe Cucumbers l, 7, 10, 81 and 84 cichoracearum Venturia Apples 7,l9 and 81 inaequalis Alternaria Tomatoes 34 and 79 solani Erysiphe Oats4 and 7 graminis Botrytis Broad 19, 26, 39 and 79 fabae Beans Thecompounds of Examples 5, 6, 11, 16, 26, 81, 82 and 84 have been found tobe active against the soilborne disease Rhizoctonia solani.

The fungicidal 4-aryl-hydrazono compounds of the present applicationwere first described as 4-arylazo compounds in Serial No. 147,741. Thisis due to the fact that the compounds in question can exist in differenttautomeric forms. However, in the solid state in which the productsdescribed herein are made, these products are more correctly identifiedwith the aryl-' hydrazono structure rather than the tautomeric arylazostructure attributed to these same compounds in Ser. No. 147,741.

What we claim is:

l. A fungicidal composition comprising, as the essential activecomponent, a fungicidally effective amount of a 2-isoxazolin-5-onewhich, in one tautomeric form, has the formula:

wherein R is selected from the group consisting of carboxy-methyl,carboxyethyl, alkyl of one to six carbon atoms, hydroxy-alkyl of one tosix carbon atoms, alkoxycarbonylalkyl of one to four carbon atoms,cyanoalkyl of one to six carbon atoms, and halo-alkyl of one to sixcarbon atoms; and R is selected from the group consisting of phenyl andnaphthyl radical, and a carrier for said active component, said carrieris selected from the group consisting of solid inert diluents and liquidinert diluents.

2. A fungicidal composition according to claim 1 wherein the activeingredient is one where R is methyl and R is chlorophenyl.

3. A fungicidal composition according to claim 1 wherein the activeingredient is one where R is methyl and R is lower alkylphenyl.

4. A fungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-phenylhydrazono-2-isoxazolin-5-one.

5. A fungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-(2'-methylphenylhydrazono)-2-isoxazolin-5-one.

6. A fungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-(2- chlorophenyl-hydrazono)-2-isoxazolin-5-one.

7. A fungicidal composition according to claim I wherein the activeingredient is 3-methyl-4-(3'- chlorophenylhydrazono)-2-isoxazolin-5-one.

8. A fungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-(4- chlorophenylhydrazono)-2-isoxazolin-5-one.

9. A fungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-(2'-methyl-4'-chlorophenylhydrazono)-2-isoxazolin-5-one.

10. A fungicidal composition according to claim 1 wherein said activeingredient is in the form of an alkali metal salt.

11. A composition according to claim 1 wherein the carrier is a solidinert diluent which is in powdered form.

12. A composition according to claim 1 wherein the carrier is anon-phytotoxic liquid.

13. A fungicidal seed-dressing composition comprising a solution of analkali metal salt of 3-methyl-4- phenylhydrazono-2-isoxazolin-5-one in anonphytotoxic solvent.

14. A fungicidal composition according to claim 13 in which the alkalimetal salt is the sodium salt and said salt is present in a proportionof about 25% w/v.

15. A method combatting plant pathogens which comprises applying to thehabitat of said pathogens a fungicidally effective amount of a2-isoxazolin-5-one which in one tautomeric form, has the formula:

II N GO wherein R is selected from the group consisting ofcarboxy-methyl, carboxyethyl, alkyl of one to six carbon atoms,hydroxy-alkyl of one to six carbon atoms, alkoxycarbonylalkyl of one tofour carbon atoms, cyanoalkyl of one to six carbon atoms, and halo-alkylof one to six carbon atoms; and R is selected from the group consistingof phenyl and naphthyl radicals.

16. The method of claim 15 wherein said fungicide is applied to thefoliage of a plant susceptible to said pathogens.

17. The method of claim 15 wherein said fungicide is applied to seedfrom which a plant susceptible to said pathogens is grown.

18. The method of claim 15 wherein said fungicide is applied to soil inwhich a plant susceptible to said pathogens is grown.

19. A method of combatting plant pathogens according to claim 15 whereinplant seed is treated with said 2-isoxazolin-5-one and the pathogens areselected from the group consisting of Pythium ultimum, Fusariumculmorum, Xanthomonas malvacearum and Tilletia cams.

20. A method of combatting plant pathogens according to claim 15 whereinfoliage susceptible to said pathogens is treated with, said2-isoxazolin-5-one, said pathogens being selected from the groupconsisting of Piriculan'a oryxae, Plasnwphora vitocola, Erisiphecichoraccarum, Venturia inaequalis, Alternaria solam', Brysiphe graminiaand Botyritisfabae.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent. No. DatedAugust 8, 1972 Inventor) Michael Joseph Augustine Geoghegan et a1 It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

In the heading of the patent, add:

-[30] Foreign Application Priority Data November 2, 1960 Great Britain..37645/60 July 31, 1961 Great Britain. .27676/6l-- Line 2 of theabstract, "and one" should be -one and-- Colrgn 11, line 49,"Pirisularia" should be --Piricularia-- Column 12, line 24, "radical"should be -radicals-- cichoracearum, Venturia inaequalis, Alternariasolani,

Ervsiphe graminis and Botrytis fabae.-

Signed and sealed this 1st day of April 1.975.

(SEE-1L) Attest:

C. I-"ZARSI-KALL ANN Commissioner of Patents and Trademarks RUTH C.ELISQN attesting Officer

2. A fungicidal composition according to claim 1 wherein the activeingredient is one where R is methyl and R1 is chlorophenyl.
 3. Afungicidal composition according to claim 1 wherein the activeingredient is one where R is methyl and R1 is lower alkylphenyl.
 4. Afungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-phenylhydrazono-2-isoxazolin-5-one.
 5. Afungicidal composition according to claim 1 wherein the activeingredient is3-methyl-4-(2''-methyl-phenylhydrazono)-2-isoxazolin-5-one.
 6. Afungicidal composition according to claim 1 wherein the activeingredient is3-methyl-4-(2''-chlorophenyl-hydrazono)-2-isoxazolin-5-one.
 7. Afungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-(3''-chlorophenylhydrazono)-2-isoxazolin-5-one.8. A fungicidal composition according to claim 1 wherein the activeingredient is 3-methyl-4-(4''-chlorophenylhydrazono)-2-isoxazolin-5-one.9. A fungicidal composition according to claim 1 wherein the activeingredient is3-methyl-4-(2''-methyl-4''-chlorophenylhydrazono)-2-isoxazolin-5-one.10. A fungicidal composition according to claim 1 wherein said activeingredient is in the form of an alkali metal salt.
 11. A compositionaccording to claim 1 wherein the carrieR is a solid inert diluent whichis in powdered form.
 12. A composition according to claim 1 wherein thecarrier is a non-phytotoxic liquid.
 13. A fungicidal seed-dressingcomposition comprising a solution of an alkali metal salt of3-methyl-4-phenylhydrazono-2-isoxazolin-5-one in a non-phytotoxicsolvent.
 14. A fungicidal composition according to claim 13 in which thealkali metal salt is the sodium salt and said salt is present in aproportion of about 25% w/v.
 15. A method combatting plant pathogenswhich comprises applying to the habitat of said pathogens a fungicidallyeffective amount of a 2-isoxazolin-5-one which in one tautomeric form,has the formula: wherein R is selected from the group consisting ofcarboxy-methyl, carboxyethyl, alkyl of one to six carbon atoms,hydroxy-alkyl of one to six carbon atoms, alkoxycarbonylalkyl of one tofour carbon atoms, cyanoalkyl of one to six carbon atoms, and halo-alkylof one to six carbon atoms; and R1 is selected from the group consistingof phenyl and naphthyl radicals.
 16. The method of claim 15 wherein saidfungicide is applied to the foliage of a plant susceptible to saidpathogens.
 17. The method of claim 15 wherein said fungicide is appliedto seed from which a plant susceptible to said pathogens is grown. 18.The method of claim 15 wherein said fungicide is applied to soil inwhich a plant susceptible to said pathogens is grown.
 19. A method ofcombatting plant pathogens according to claim 15 wherein plant seed istreated with said 2-isoxazolin-5-one and the pathogens are selected fromthe group consisting of Pythium ultimum, Fusarium culmorum, Xanthomonasmalvacearum and Tilletia caries.
 20. A method of combatting plantpathogens according to claim 15 wherein foliage susceptible to saidpathogens is treated with said 2-isoxazolin-5-one, said pathogens beingselected from the group consisting of Piricularia oryxae, Plasmophoravitocola, Erisiphe cichoraccarum, Venturia inaequalis, Alternariasolani, Brysiphe graminia and Botyritis fabae.